npm test should not execute outside commands.

[mshima]

Overview of the issue

npm test should mock spawn functions.

Outside commands are not reproducible due to the environment.
Generators should run mocked functions that calls outside commands to avoid problems like #22474.

Related issues

#22474

Suggest a Fix

Switch from shelljs and child_process to generator's spawn[Command][Sync] methods.
Mock generator's spawn methods.

JHipster Version(s)

JHipster configuration

Entity configuration(s) entityName.json files generated in the .jhipster directory

Browsers and Operating System

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